import java.util.Scanner;

class circlecalculate {
    public static final double Pi = 3.14159265;
    public double r;

    public circlecalculate() {
        // No need to pass an initial value for r, it will be set in the cal method
    }

    public void cal() {
        Scanner scanner = new Scanner(System.in);
        System.out.print("请输入圆的半径: ");
        r = scanner.nextDouble();
        System.out.println("S=" + r * r * Pi + ";");
        System.out.println("C=" + Pi * r * 2);
        scanner.close();
    }
}

public class Circle {
    public static void main(String[] args) {
        circlecalculate ci = new circlecalculate(); // No need to pass an initial value for r
        ci.cal();
    }
}
